When experts assert that up to ten percent of fresh food packages do not fulfill the applicable quality requirements, they usually refer to cosmetic or functional deficiencies. This, for example, applies to creased labels, wavy packaging film or defective peel-off ends.
An annoying situation for retailers: The content of a given package is just as fresh as the content of the products with flawless packaging; nonetheless, customers will leave these products in the freezer. This constitutes a typical case in which X-ray and camera supported inspection systems can show their advantages.
Labels put to the test: The camera-supported Bizerba Vision system
Bizerba has many years of experience using inspection systems and, in addition to classic metal detectors, it also offers X-ray scanners and camera systems. The Bizerba Vision System (BVS) is a camera-supported test system for food producers which permits
- to carry out automatic sealing seam inspections,
- to detect leaks and contaminations on the packaging,
- to check the accuracy of label positions, barcodes and the sell-by-date
- and to check if the texts on all labels are correct with the help of automatic text recognition.
To detect incorrect texts on the packages, in particular, is of fundamental importance for manufacturers. Many products only differ in a tiny detail, such as the type of marinade used, for example. Therefore, any mistakes which might occur in production can have serious consequences, e.g. for allergy sufferers. Incorrectly labeled products are immediately detected by the BVS and removed from the production process with the help of pushers using compressed air.
X-ray scanners ensure transparency: Glass, PVC and stone particles can be detected reliably.
Metal detectors are classical and indispensable elements of quality assurance. Efforts have to be undertaken every day to prevent the worst possible disaster: a consumer injured by a foreign matter in food. However, the performance of conventional detectors quickly reaches its limits - for example when metal particles in aluminum cans or foreign bodies consisting of non-metallic materials have to be identified. The Bizerba X-ray scanner XRE enables manufacturers to detect PVC, wood and glass in products.
The principle behind the system is relatively simple. An X-ray pipe is mounted below the conveyor belt. The rays then hit the product and are absorbed to different degrees by the different components. Above the conveyor belt there is a high-resolution detection unit which converts the radiation which has passed through into an electric signal. Finally, this is used to create a digital X-ray image with the help of a visualization software. Admissible metal bodies such as aluminum clips on ends of sausages are ignored in this process.
Unlike conventional metal detectors, the X-ray scanner XRE can also be used to detect glass, ceramic and stone particles. Moreover, all those parts which absorb the X-rays differently than the surrounding product because of their density, chemical composition or mechanical dimension can be identified.
The device has a capacity of up to 600 packages per minute and, in this process, it detects cracks and air pockets and even carries out a completeness check. This makes it easy to check whether a cardboard tray contains the full number of yogurt cups, for example.